KR20070052277A - Processes for preparing organic pigment dispersions and ink - Google Patents

Abstract

Methods of making organic pigment dispersions, such as flush pigments or ink products, include the steps of introducing a stable water containing pigment dispersion, an organic medium and a destabilizing agent into a pair of screw extruders, the stable water containing pigment dispersion, an organic medium And mixing the destabilizing agent to produce a pigment flush layer and a water layer, and removing at least a portion of the water layer. The pair of extruders for carrying out the flush process includes a zone for inputting and flushing, a zone for removing water, a zone for rinsing or flushing the crude organic pigment dispersion with water and removing the rinsed water. Additives may be added, thereby completing a colored product such as an ink product, a masterbatch or a toner.

Description

Organic pigment dispersion and ink manufacturing method {PROCESSES FOR PREPARING ORGANIC PIGMENT DISPERSIONS AND INK}

The present invention relates to a process for the preparation of coloring compositions, such as organic pigment dispersions comprising pigment flushes and ink compositions. The present invention also relates to an ink base and a method for producing the finished ink composition.

In the synthesis of many organic pigments, a pigment slurry is prepared by mixing in a dilute water soluble medium, and then the slurry is filtered by a filtration compressor to concentrate the pigment. The compressed agglomerates prepared are made of a pigment in the form of particles dried through a drying process, or the pigment particles are transferred from the water-soluble agglomerate to the oil or resin layer by a flush process using an organic medium such as oil or resin. The flush process takes additional time and material compared to the process of simply drying the pigment. However, when pigments are used in inks or paint compositions, the pigments must be well dispersed in a suitable organic medium to achieve the desired color and to ensure stability. The flush process is more advantageous because the pigment can be transferred to the organic medium without the intermediate step of drying the pigment separately or grinding the pigment in the organic medium to produce a pigment dispersion.

Conventionally, pigment flushes have usually been produced in a batch process. In the batch process, for example, the compacted mass is kneaded together with an organic substance such as oil or resin using a sigma blade mixer or dough mixer. This moves the pigment particles from the water soluble layer to the organic medium layer and makes the water a separate water soluble layer. The separated water is discarded and the pigment dispersion in the organic solvent can be used as a pigment paste in the preparation of inks or paints.

The batch process has many disadvantages. To achieve maximum yield in the flushing process, the steps of adding organics such as varnishes, kneading to displace water, and discarding water must be repeated several times. This is a labor intensive process that requires careful monitoring. In addition, the ash is heated and vacuumed to remove residual water. For most pigments, the heat applied in the process of removing residual water causes the pigment to discolor. Since the degree of heat applied to each batch is different, it is difficult to accurately and reliably reproduce pigments of the same color from each batch. One of the most significant disadvantages of the batch process is that the content of pigment and solids in the compacted mass is not constant for each batch. In addition, the process is time consuming and inefficient. Even if the water is removed by vacuum, it is difficult to lower the water content to 3% by weight or less. Moreover, the content of the pigment in the compacted mass and thus the content of the pigment in the flush is not constant.

Continuous processes have been proposed for producing pigment flushes using compressed mass. Specifically, the processes are described in US Pat. Nos. 6,273,599, 6,305,838, and 6,348,091. Each of these patents is incorporated herein by reference. The patents have very successfully solved some of the disadvantages arising from the batch flush process. US Pat. No. 5,262,268 describes a process for producing toner in a pair of screw extruders using a compressed mass.

The present invention provides a process for the continuous production of organic pigment dispersions such as pigment flushes or ink products. In this method, the pigment is introduced into a pair of screw extruders in the form of a pigment dispersion in a stable aqueous solution. The method can solve the problem of different pigments and colors for each ash and different solids in the compacted mass. A stable dispersion is one that has a long shelf life without sinking or being able to spread. The stable pigment dispersion may be destabilized by a destabilizing agent.

In one embodiment of the invention, the stable pigment dispersion is fed to the extruder at a predetermined rate with a destabilizing agent that precipitates the dispersed pigment. An organic medium comprising organic components selected from solvents, varnishes, oils, polymers, dispersants and / or resins is also fed to the extruder. The destabilized or precipitated pigment and organic medium are mixed in the first zone of the extruder to wet the pigment with the organic medium and replace water from the pigment to produce an organic pigment dispersion such as an unrefined pigment flush. At least a portion of the substituted water is removed in the second zone of the extruder. The second zone of the extruder comprises a port for removing said substituted water, in particular for draining water. Preferably, the second zone comprises a weir that retains the organic pigment dispersion or pigment flush in the second zone for a time sufficient to remove most of the substituted water from the unpurified flush. The third zone includes additional ports for introducing rinse water to remove salts or other by-products from the destabilized or precipitated pigments or to drain the rinsed water. The extruder includes a fourth zone having one or more vacuum ports capable of removing water remaining in the organic pigment dispersion or pigment flush. The extruder may comprise additional zones for additionally introducing additives for preparing the final pigment dispersion, for example resins, oils, solvents, dispersants, waxes, surfactants and additives of pigments or inks.

Another embodiment of the present invention provides a method for continuously producing an ink base or finished ink from a pigment dispersion in a stable aqueous solution. The method comprises the steps of producing a pigment flush and at some point before the final outlet of the extruder, preferably at a point after the optional vacuum zone, varnish, colored color control components, solvents and / or additives. At least one additional step of introducing one or more additional ink components such as these. In this way, an ink base or a finished ink composition can be prepared.

In one embodiment, the pigment dispersion of the stabilized aqueous solution has a pigment content of at least about 25% by weight or more.

In another embodiment, the pigment dispersion of the stabilized aqueous solution is stabilized by an ionic dispersant and the destabilizing agent is an ionic agent. In one embodiment, the ionic dispersant has carboxylic acid groups in salt form to stabilize the dispersion of the aqueous solution. In addition, the dispersion of the aqueous solution is destabilized with protic acid or Lewis acid.

In one embodiment of the first zone, the stabilized pigment dispersion and destabilizing agent are introduced into the extruder at a first point, ie the first barrel. The stabilized pigment dispersion and destabilizer are mixed in the extruder to produce an aqueous solution of destabilized pigment material. The organic medium is introduced into the extruder in a barrel located at a second point, i.e., downstream of the first zone, and mixed with the destabilized pigment material to produce an organic pigment dispersion layer and a water layer.

In another embodiment of the first zone, the stabilized pigment dispersion, destabilizer and organic medium are all introduced together into the first barrel of the extruder.

In one embodiment of the process, the pigment dispersion in a stable aqueous solution is substantially destabilized by the destabilizing agent before the organic medium is introduced into the extruder. In another embodiment, the organic dispersion is introduced into the extruder before the pigment dispersion of the stable aqueous solution is substantially destabilized in the extruder.

In some embodiments of the present invention, toner products are prepared using a toner vehicle, such as a low melting point solid polymer or resin, with the organic medium.

In some embodiments of the present invention, the organic medium may optionally include a homopolymer of polyethylene, a copolymer of polyethylene, an acrylonitrile butadiene styrene copolymer, polybutyene, polystyrene, polyphenylene oxide, polycarbonate, polypropylene, and the like. Master batches are prepared using low melting point resins such as hydrocarbons, terpene resins or rosin materials.

As used herein, "one" means "at least one" and, where possible, plural. When “about” is used in a numerical value, it means a value that is close to or reasonably close to the numerical value, meaning that some minor inaccuracy in the numerical value is allowed in the calculation or measurement. If the inaccuracies caused by the "about" cannot be understood in the same general sense to those of ordinary skill in the art for any reason, then the "about" as used herein is This means a deviation of up to 5% from that figure.

1 is a schematic view showing the arrangement of an extruder for carrying out one embodiment of the invention.

FIG. 2 is a schematic view showing another configuration of the first four barrels of the extruder of FIG. 1.

Preferred embodiments of the invention described below are intended to illustrate the invention and are not intended to limit the invention and its use.

In the process of continuously producing the organic pigment dispersion, pigment flush, ink product or other colored product of the present invention, a stable pigment dispersion containing water is introduced into a pair of screw extruders to destabilize in the extruder. The destabilized or precipitated pigment is mixed with or diffused into the organic medium. The separated water layer can be removed from the organic pigment dispersion layer.

One embodiment of the preferred extruder arrangement includes at least four zones and optionally a fifth zone or more zones. In the first zone, represented by barrels 1 to 3 shown in FIG. 1, the pigment dispersion, the organic medium and the destabilizing agent in a stable aqueous state are fed to the extruder (barrel 1), and the materials are mixed with each other to obtain the pigment. Destabilize or precipitate and remove the pigment from the water soluble layer by spreading the pigment from the water soluble layer to the organic layer in a flush process (barrels 2 and 3). The destabilizing agent is supplied in a separate state, preferably after the pigment dispersion is fed. In the second zone, represented by barrels 4 and 5, at least a portion of the water substituted in the flushing process in the first zone is drained away from the extruder. In the third zone, represented by barrels 6, 7A, 8 and 7B, which are the ends of barrel 5, the salt form contained in the pigment dispersion of the salt and the aqueous solution precipitated by the interaction of the destabilizing agent by introducing water for rinse. Impurities such as dispersible resins can be washed off from organic pigment dispersions or pigment flush mixtures. The rinsed water can be removed by draining it from the extruder through the port. In the fourth zone, represented by barrels 9-11, a vacuum port is used to apply a vacuum to remove residual water in the form of water vapor to dewater the organic pigment dispersion or pigment flush. The fourth zone may include an inlet (port) for introducing organic pigment dispersions, flush products, additives that can be used in inks or colored products, resins, and the like. The fifth zone, represented by barrels 12 to 14, is an optional zone, where it is possible to further mix the organic pigment dispersion or flush or further add other components to the organic pigment dispersion or flush as in the fourth zone. Additional ports may be used in the fourth zone and / or the optional fifth zone to introduce ink components or other necessary components. In this way, ink bases, finished ink compositions or other pigment products can be produced. Each zone can be heated or cooled to an appropriate temperature to maintain optimal mixing and color of the pigment. The product can be cooled before it is finally discharged.

FIG. 2 illustrates another embodiment of a first zone of the extruder of FIG. 1. In this other embodiment, the pigment dispersion and the destabilizing agent of the stable aqueous solution are introduced into barrel 1 and mixed. As shown in FIG. 2, an organic medium such as a polymer or a dispersant is introduced into barrel 2. The pigment may destabilize or precipitate in barrel 1 to form a material such as a thick compacted mass. The destabilized pigment is mixed with the organic medium in barrels 2 and 3 so that pigment is drawn into the organic medium. This forms an organic pigment dispersion and a substituted water layer. The process of treating the organic pigment dispersion is carried out via the second, third, optional fourth and optional fifth zones described above.

In a first step according to the first embodiment of the process, a stable aqueous pigment dispersion, organic medium and destabilizing agent are introduced into the first zone of the extruder. Stable water-based pigment dispersions can be prepared using any of a number of known methods. The pigments used to prepare the stable aqueous pigment dispersions can be used, for example, in the form of aqueous slurry, compacted mass, unpurified pigment in dry state, activated and unpurified pigment or dry pigment. The pigments are stabilized by polymeric, oligomeric and / or monomeric dispersants or combinations of these dispersants in aqueous dispersions. The dispersant, the base for salting the dispersant, and water (only if necessary) are mixed with the pigment to form a stable water-containing pigment dispersion comprising the desired amount of pigment.

Any one of a number of organic pigments can be used to prepare the stable dispersion. Suitable examples of organic pigments include lithol reds (e.g. calcium litho red, barium litho red), rubin reds, and azo pigments such as naphthol red, orange and brown, monoarylides, dia Diarylide pigments such as lylide yellow, phthalocyanine blue and green pigments, azomethine pigments, methine pigments, anthraquinone pigments, perinone pigments, perylene pigments, diketopyrrolopyrrole pigments, thioindigo pigments , Iminoisoindolin pigments, iminoisoindolinone pigments, quinacridone pigments such as quinacridone red and violetene, flavantron pigments, indanthrone pigments, anthrapyrimidine pigments, carbazole pigments such as carbazole violet , Benzimidazolone yellow, tolyl orange, naphthol orange, quinophthalone pigment, and the like, but are not limited thereto.

  Examples of useful ionic dispersants that may be used to prepare the pigment dispersions of the stable aqueous solution include lauroyl acid, tall oil fatty acid, oleic acid, linoleic acid, linolenic acid ( linolenic acid), fatty acids such as palmitic acid, stearic acid, alkylbenzenesulfonates, alkylsulfonates such as dioctylsulfosuccinate, ionic resins such as alkyd resins, polyesters, rosin, unsaturated acids (e.g. male Acids, fumaric acid, acrylic acid, methacrylic acid, crotoninic acid), dimerized rosins, disproportionated rosins, hydrogenated rosin, phenol-modified rosin, maleic acid or fumaric acid Modified polymer, vinyl resin having acid functional group including acrylic polymer having acid functional group, phenol-acrylic polymer, styrene-maleic anhydride (SMA) polymer, low molecule Sensitive to the acid functionality of the polyurethane, and having pH or preparing a dispersion which can be destabilized by the other material in the extruder may be a useful other stabilizing material. The dispersant may be used in a stable combination thereof. The ionic resin is salted in combination with a suitable counterion to provide solubility or dispersibility in water. Dispersants with acid functionality can be salted with bases such as sodium hydroxide, ammonium hydroxide, potassium hydroxide monoalkylamines and dialkylamines. The aqueous dispersion further comprises organic pigment compositions or other additives useful for making a flush color, such as oils (vegetable oils and petroleum), antioxidants, antifoams, surfactants, so-called pigments, hyperpigmentary dispersants and non-dispersion resins, and the like. It may include.

The stabilized aqueous pigment dispersion preferably has a pigment content of at least about 25% by weight or more, more preferably about 35% by weight or more. The pigment content of the stable dispersion depends on the type of pigment and dispersant chosen, and may exceed about 50% or even about 60% by weight, and the water may be very low. The organic pigment dispersion typically has a pigment content in the range of about 25% to about 50% by weight. The stabilized aqueous pigment dispersion may comprise about 6 to about 40 parts by weight of an ionic dispersant based on 100 parts by weight of the pigment.

The stable aqueous pigment dispersion can be prepared by extension of pigment synthesis. That is, it can be prepared by treating the pigment slurry or postdispersing the compacted mass or dried pigment with a high speed disperser, rotor-stators, basket mill or pigment grinding mill.

The organic medium in which the pigment is dispersed or flushed has sufficient hydrophobicity to form a water-insoluble layer during the process. The type of organic material suitable for preparing the pigment flush is well known in the art. The organic medium may be fed to the same port as the stabilized water containing pigment dispersion, but is preferably fed to the extruder through a separate separate port.

Typical types of resins or oils that can be used to flush varnishes include alkyd resins, phenolic resins, polyesters, hydrocarbon resins, maleic acid resins, rosin modified varnishes thereof, polyamide resins, polyvinyl chloride resins, vinyl acetate resins, Vinyl chloride / vinyl acetate copolymer resins, chlorinated polyolefins, polystyrene resins, acrylic resins, polyurethane resins, ketone resins, vegetable oils including flaxseed oil, soybean oil, bereaved oil, coconut oil, tung oil ), Mineral oil, and the like, and the like. Combinations of the above resins and oils may also be used. The resin, oil or a combination thereof may be combined with a hydrophobic organic solvent or solution comprising a high boiling petroleum distillate.

Typical types of organic materials that can be used to prepare organic pigment dispersions used as toners include esterification reactions of polyamides, epoxides, diolefins, polyurethanes, vinyl resins, and diols, including dicarboxylic acids and diphenylols. The polymer product of the above is mentioned, It is not limited to these. Among the suitable vinyl resins are styrene, p-chlorostyrene, vinyl naphthalene, ethylene, propylene, butylene, isobutylene, vinyl chloride, vinyl bromide, vinyl fluoride, vinyl acetate, vinyl propione as well as styrene butadiene copolymers. Nate, vinyl benzoate, vinyl butyrate, methyl acrylate, dodecyl acrylate, n-octyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methylalphachloroacrylate, methyl methacrylate, ethyl methacrylate Butyl methacrylate, acrylonitrile, methacrylonitrile, acrylimide, vinyl methyl ether, vinyl isobutyl ether, vinyl ethyl ether, vinyl methyl ketone, vinyl hexyl ketone, vinyl isopropenyl ketone, vinylidene chloride, Vinylidene chlorofluoride, N-vinyl indole and N-vinyl pyrroli Money, etc.

Typical types of organic materials that can be used to prepare masterbatches include polyethylene homopolymers and copolymers, polypropylene homopolymers and copolymers, acrylonitrile butadiene styrene copolymers, polystyrenes, polyphenylene oxides, polycarbonates, polyacrylates And polymers such as but not limited to these. These polymers can be used in combination with low molecular weight resins such as hydrocarbon resins, rosin or terpene resins.

In the first embodiment, the stabilized aqueous pigment dispersion is fed with the organic medium to the first zone of the extruder and the destabilizer is fed separately. The aqueous pigment dispersion, precipitant and organic medium can be adjusted and added at a constant rate to produce a constant flush product. For example, the materials may be supplied separately from lines or tanks, which may be provided with a stirrer or metered (eg) by a pump.

Preferably, the organic medium, stable water containing pigment dispersion and destabilizing agent are each introduced at a very constant rate. The relative amounts of pigments of the organic medium and the aqueous pigment dispersion to perform the optimal process can be determined based on the particular material selected, but in general the amounts are the same as would be expected in conventional batch flush processes. For example, the amount of organic medium introduced per unit time may be about 0.6 to about 3 times the amount of solid pigment introduced in the same unit time. The ratio of the organic medium to the solid pigment can be adjusted according to factors known in the art such as the kind of pigment, the kind of organic medium, and can be controlled by automated process control methods.

Aqueous pigment dispersions are destabilized by the addition of destabilizing agents to render the pigment free or precipitate. The destabilizing agent may be selected based on destabilizing properties of the pigment dispersion. For example, when the pigment dispersion is prepared using a pH sensitive dispersant such as anionic resin in salt form, destabilizing agents which can change the pH to acidic pH are effective. Typical types of destabilizers that may be added include protic and Lewis acids such as hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid, formic acid and aluminum chloride. These destabilizing agents can be used in combination, and other weak acids such as calcium chloride and strontium chloride can be used in combination with strong acids. Destabilizers are appropriately selected so that salts produced by the interaction of the destabilizing agent with the water-containing pigment dispersion and excess destabilizing agent can be removed by washing or evaporation.

In a second embodiment of the invention, the stabilized aqueous pigment dispersion and destabilizing agent are introduced into the extruder in separate feeds and mixed, and then the organic medium is added at the downstream point. In this embodiment, the aqueous pigment dispersion is first substantially destabilized by the destabilizing agent before the organic medium is added. The destabilized water soluble pigment dispersion has a high viscosity, which is advantageous for mixing with high viscosity polymer melts such as those used to prepare masterbatches.

The pair of screw extruders used in the preferred embodiment of the method is shown in FIG. 1. The first zone includes a threaded member for mixing the destabilized water soluble pigment and the organic medium. The destabilized water soluble pigment may be treated as a high solid compacted mass in the extruder. The first zone should include one or more members thereof that can mix with high shear stress. Referring again to FIG. 1, barrel 1 has four separate ports for introducing a stable water soluble pigment dispersion, alkyd, varnish and acid destabilizer (in preferred order). Barrel 1 includes feed screw members. Barrel 2 includes screw and transfer screw members for mixing or kneading in combined form. Barrel 3 includes high shear stress mixing and transfer screw members in a combined form. Barrels 2 to 4 may be heated with an oil jacket maintained at about 60 ° C. The pigment mixture in barrel 2 may be about 45 ° C., but may reach up to nearly 90 ° C. by heat generated by flush shear stress.

In another embodiment shown in FIG. 2, barrel 1 has two separate ports for introducing a stable water soluble pigment dispersion and a destabilizing agent, and barrel 2 has two separate ports for introducing a polymer and a dispersant. Have Optionally, an additional barrel may be introduced before barrel 4 to mix longer before separating the aqueous layer.

In one preferred embodiment of the invention, the screw in the first zone is tapered from the deep channel used in the site with the supply port to the shallow channel located downstream of the first zone. The length of the first zone of the extruder in which the destabilized water soluble pigment dispersion and the organic medium are mixed is long enough for the pigment to be completely flushed. The rotational speed of the screw is a factor for an efficient flush process. A preferred range of the rotational speed of the screw is from about 150 rpm to about 550 rpm, and a more preferred range of the rotational speed is from about 250 rpm to about 350 rpm. Because of the high pigment concentration, the flush zone of the extruder is relatively short compared to the filler zone required at low water soluble pigment concentrations.

The substituted water and the crude organic pigment dispersion, ie the pigment flush, leads to the second zone of the extruder, where at least a portion of the substituted water is removed. Preferably, a substantial portion of the substituted water is removed in the second zone, more preferably at least about 80% or more, even more preferably at least about 90% or more, and even more preferably, adhere to the pigment flush. All but the remaining water is removed. Referring to FIG. 1, barrel 4 includes an outlet for removing the replaced water in the flush zone, and preferably includes an outlet for draining the water. The water can be removed by other means, but gravity drainage is the simplest and therefore preferred method. The outlet or port includes a length that is separate from the screw that is rotated by the motor and, as described in US Pat. Nos. 6,273,599, 6,305,838 and 6,348,091, the motor has a relatively high viscosity during water drainage. The flush containing pigment is driven to return to the barrel zone.

The second zone is downstream of the drain or outlet so as to retain the organic pigment dispersion or pigment flush for a sufficient time such that most of the substituted water from the unpurified organic pigment dispersion or flush mass can be removed. It has a dam. The weir allows the kneaded pigment / organic medium to stay around the pot for a time sufficient to drain more of the substituted water from the kneaded pigment. The mixing of the pigment and the organic medium is carried out in part at the bank of the extruder and stays at the bank until the drainage of water is complete and is carried to the next zone by the screwing action. Such weirs are described in more detail in US Pat. Nos. 6,273,599, 6,305,838, and 6,348,091. Briefly, barrel 5 of FIG. 1 is threaded so that at least one threaded member is tightened in the reverse direction downstream of the drain, providing sufficient reverse flow and allowing the materials to fill the area containing the outlet. The force flowing in the reverse direction causing the dam effect may be limited because there is no compression. Because compaction tends to form an emulsion of the water soluble layer and the organic layer, which prevents the separation of water from the organic layer. The reverse flow allows material to accumulate before it pulls over the weir or is pulled by a forwardly rotating screw located further downstream. Water does not participate in the forwardly rotating screw and does not flow over the accumulated materials. Instead, the water is drained while staying in the second zone. Unlike the prior art, since most of the water is drained from the flush into the liquid phase rather than evaporating, the final result is a very low salt concentration. Thus, the bank improves the purity of the final result.

As shown in FIG. 1, water for rinse in a third zone is introduced into the crude flush to wash off water soluble impurities. In particular, impurities such as salts precipitated by the action of the destabilizing agent and dispersant resins in the form of salts of the water-soluble pigment dispersion are removed from the pigment dispersion or flush mixture which may remain in the crude dispersion or flush. The rinse water can also remove impurities contained in the aqueous pigment dispersion. Thus, the aqueous pigment dispersion may comprise high or low concentrations of impurities or salts that can be washed in the extruder. Generally, the water may be added at a rate of about 60 to about 150% of the rate of adding the pigment into the extruder. The rinse water is preferably introduced through the top photo of the extruder and can be mixed with the crude flush material in one or more barrels of the third zone. It may then be removed by draining the liquid from the port of the extruder, as in the second zone. Also, as in the second zone, it is preferable to create a weir by arranging the screw members which tighten in the reverse direction, ie in the left hand direction, downstream of the port or drain. Although the case of installing a weir in both the second and third zones is described, at least the third zone is at least such a weir to minimize water remaining in the organic pigment dispersion or flush product present in the third zone. Must include. In one preferred embodiment of the invention, the screw in the third zone is tapered from the deep channel used in the part with the supply port to the trailing part of the third zone, ie the shallow channel in the downstream part. The third zone of the extruder, in which the crude flush pigment and wash liquor are mixed, has a length sufficient to remove unwanted insoluble impurities from the pigment.

In FIG. 1, the third zone begins with an inlet for introducing rinse water at the end of barrel 5. Barrels 6 and 7A have mixing and delivery screw members, and barrel 8 has mixing outlets for the rinse water, such as the outlet described in barrel 4. One or more mixing members may comprise a plurality of dough discs. Barrel 7B may include one or more screw members that tighten in the reverse direction. Barrels 5 to 8 may be covered with an oil jacket maintained at a temperature of about 60 ° C. The pigment mixture in barrel 5 may be at a temperature of about 80 ° C. or higher, and in barrel 7 the pigment mixture may reach high up to a temperature of about 120 ° C.

In FIG. 1, the fourth zone is shown by barrels 9 to 11. Barrels 9 to 11 comprise transfer screw members and two vacuum ports for removing residual water in the form of water vapor. The fourth zone is an optional zone, but is more preferred. The fourth zone also has one or more vacuum ports capable of removing residual water that clings to the pigment flush. The water is removed in the form of water vapor. Suitable vacuum ports that can be used in the extruder are known and rotated by a motor in the vacuum port to help retain the flush in the extruder, as described in US Pat. Nos. 6,273,599, 6,305,838, and 6,348,091. It is common to include the part containing the screw to make. It is common for a vacuum pump to be connected to the vacuum port to provide a low pressure condition. In order for the flush material to have the shape of a thin film to improve the efficiency of vacuum dewatering, the screw used in the vacuum region preferably has the form of a shallow channel. Figure 1 shows the same vacuum ports on successive extruder sites. Barrels 9 to 11 may be covered with a hot oil jacket maintained at a temperature of about 40 ° C. Lower jacket temperatures and evaporation should be expected to cool the material in the extruder. In barrel 9 it may be at a temperature of about 70 ° C. or higher, and in barrel 11 it may be as high as about 90 ° C.

1 shows an inlet through which barrel 9 can be added additives, resins, solvents or other materials as required. Thus, desired flush or ink product compositions, toners, masterbatches or other colored compositions can be prepared. Similarly, barrels 12 and 13 illustrate ports in addition to solvents, varnishes, and additives, as well as other materials needed to prepare the final flush, ink product, toner, masterbatch, or other colored composition. Barrels 12 to 14 show coolant jackets for cooling the product before final discharge. The coolant jacket may be about 35-40 ° C., so that the resultant present in the extruder may be at a temperature of about 65 ° C. or less. The last section of the extruder is of the length necessary to obtain the desired material with effective mixing and to cool the resultant.

The manufacturing method of the present invention as described above can produce a product of less constant quality and more constant adjustment of the parameters during the flushing process.

The pigment flush prepared according to the production method of the present invention may be used to prepare the ink composition by conventional methods. Alternatively, the pigment flush may be introduced at any point before the pigment flush is finally discharged in a continuous process of the present invention to introduce additional materials such as varnishes, other resins, organic solvents and / or additives to the ink base or It can be made into a finished ink composition. Preferably, the additional material may be introduced after the vacuum zone before the pigment flush is finally discharged. The flush pigment dispersion and other ink components are combined in the extruder and discharged from the extruder into the ink base or ink composition. Typical resins that can be added to ink varnishes include alkyd resins, polyesters, phenolic resins, rosins, celluloses, and the like; Derivatives thereof such as rosin-modified phenols, phenol-modified rosin, hydrocarbon-modified rosin, maleic acid-modified rosin, fumaric acid-modified rosin; Hydrocarbon resins, vinyl resins including acrylic resins, polyvinyl chloride resins, vinyl acetate resins, polystyrenes and copolymers thereof; Polyurethane, a polyamide resin, etc. are mentioned, but it is not limited to these. The resins may be used in combination. Examples of organic solvents that may be added include, but are not limited to, aliphatic hydrocarbons such as fractional distillates of petroleum, normal or isoparaffinic solvents with limited aromatic properties. The ink composition of the present invention may include many other additives well known in the art, and the additives may be used in the ink composition of the present invention so long as it does not seriously impair the advantages of the present invention. Examples of such additives include pour point depressants, surfactants, wetting agents, waxes, emulsifiers, dispersants, defoamers, antioxidants, ultraviolet absorbers, desiccants (e.g., of products comprising vegetable oils). Used in the manufacture), flow agents, other rheology modifiers, gloss enhancers and anti-settling agents, and the like. When additives are used, generally amounts of at least about 0.001% of the ink composition may be included, and amounts of about 7% or more of the ink composition may be included.

The toner prepared by the method may include additional materials such as silica, dispersant, charge control additives, stabilizers, waxes and the like, preferably they may be added after the vacuum zone.

The masterbatch produced by this method may likewise comprise additional material and may preferably be added after the vacuum zone. Examples of such additional materials include stabilizer slip additives, lubricants, nucleators, antioxidants, biocides, ultraviolet absorbers, hindered amine stabilizers, antistatic agents, neutralizing agents, tacky resins, and the like. It is not limited to these.

In one aspect of the invention, the extruder further comprises at least one monitoring device. The monitoring device continuously monitors the physical properties of the materials processed in the extruder. The apparatus compares the measured value with the value required for the physical property by measuring the physical properties of the materials treated in the extruder. The comparison results are used to adjust one or more parameters of the process.

The monitoring device keeps the product of the extruder convenient to use. In this regard, a number of properties and parameters are involved in the process of producing the organic pigment dispersion, pigment flush, ink product or other colored product in a continuous process instead of the batch process described above. Accordingly, in a process where the adjustment of process parameters is automated or semi-automated, an apparatus for continuously monitoring the properties of the materials during the process is very important in order to avoid producing enormous quantities of products which deviate from useless standards. The adjustment of the process parameters is preferably made according to certain logic and applied to the process by a computer processing unit, ie a programmable logic controller. Appropriate microprocessors to be programmed are known and need not be described further herein.

The monitoring device may comprise one or more measuring devices selected from spectrometers, viscometers, thermocouples, pH meters, turbidity meters, conductivity meters, moisture content meters, particle size analyzers and combinations thereof. The monitoring device may also include a mass flow meter, a motor amplifier meter, a motor speed and / or screw rotational speed control device, a supply speed control device for one or more supply members, a supply start and stop control device for auxiliary supply members, vacuum And a control device for one or more extruders selected from a degree control device, a device for controlling the process temperature at a particular point in the process, and a combination thereof. The monitoring device may be located at any point of the extruder in the outlet or sample loop. Preferably the monitoring device is located at the outlet of the extruder. The monitoring device may comprise a conversion device for separating off-reference material from the flow of product until the measured property value is acceptable.

Preferred types of monitoring devices and their uses are described in more detail in US Pat. No. 6,348,0941. In the production method of the present invention, it is more preferable to use such a device for monitoring one or more physical properties.

The invention can be illustrated by the following examples. The following examples are merely illustrative and do not limit the claimed scope of the invention. Unless specifically stated, all parts described are parts by weight.

Embodiment of the Invention

To produce the pigment flush, an extruder is used in which a pair of screws with a diameter of 44 mm, L / D of 56 and a rotational speed of 450 rpm are rotated together. The table below summarizes the dosing points, dosing speeds, and temperatures for the extruder as shown in the figures.

Barrel One 2-3 4 5 6-7 8 9-11 12-13 14 Action adding Mixed, suspended exhaust adding mix exhaust Vacuum dewatering adding mix supply Water-containing pigment dispersions, alkyds, varnishes, acids - - Rinse Water - - - Solvents, varnishes, additives - jacket none heating heating heating heating heating heating Cooling Temperature - - - 93 ℃ - 96 ℃ 80 ℃ 60 ℃

The first barrel of the extruder shown in the drawing adds 44% solids of aqueous blue dispersion at a rate of 117 lbs / hr, 56% acetic acid at a rate of 7.0 lbs / hr, 12 lbs of alkyd and organic vehicle. At a feed rate of / hr, the first hydrocarbon varnishes are fed together at a rate of 19.7 lbs / hr. These inputs are mixed and passed through the end of barrel 3. In barrel 4 the substituted water is drained from the pigment / varnish mass. The water should be fairly clear. Water in barrel 5 is fed to the extruder at a flow rate of 80 lbs / hr. The crude flush result and water are mixed in barrels 6 and 7A and drained from the extruder in barrel 8. Barrels 9-11 are vacuum dewatering zones where residual water is removed from the flush results in barrels 9-11.

In barrels 12 and 13, the flush is diluted by the addition of hydrocarbon varnish at a rate of 9.4 lbs / hr and hydrocarbon oil at a rate of 8.8 lbs / hr. The pigment flush is cooled. The pigment flush, hydrocarbon varnish and hydrocarbon oil are further mixed in barrel 14. The result is a flush with less than 2% water content and altered contrast.

The above production method of the present invention is used to prepare colored products such as organic pigment dispersions, ink products, masterbatches or toners. In addition, the production method of the present invention can produce organic pigment dispersions in a continuous process to produce a product of constant quality.

As described above with reference to the preferred embodiments of the present invention, those skilled in the art or those skilled in the art without departing from the spirit and scope of the present invention described in the claims below It will be appreciated that various modifications and variations can be made in the present invention.

Claims (22)

Introducing a stable water containing pigment dispersion, an organic medium and a destabilizing agent into a pair of screw extruders; Mixing the stable water containing pigment dispersion, the organic medium and the destabilizing agent together to produce a pigment flush layer and a water layer; And Removing at least a portion of the water layer. The method of claim 1, wherein the organic medium comprises one selected from the group consisting of organic solvents, varnishes, oils, resins, and combinations thereof. The flush of claim 1 further comprising the step of adding one or more ink components selected from the group consisting of varnishes, colored color adjusters, organic solvents, ink additives, and combinations thereof. A method of making a pigment or ink product. The method of claim 1, wherein the stabilized water-containing pigment dispersion has a pigment content of at least about 25% by weight or more. The method of claim 1, wherein the stabilized water containing pigment dispersion is stabilized by an ionic dispersant and the destabilizing agent is an ionic agent. The method of claim 5, wherein the ionic dispersant has carboxylic acid groups in salt form and the destabilizing agent is selected from the group consisting of protic acids and Lewis acids. Supplying a stable water containing pigment dispersion to a pair of screw extruders and destabilizing the dispersion in the extruder to produce a water soluble precipitated pigment. 8. The method of claim 7, further comprising the step of spreading the precipitated pigment into an organic medium in the extruder. Inlets for introducing a water soluble pigment dispersion, destabilizing agent and organic medium, feed screw members, high shear stress mixed screw members, and transfer member for transferring the pigment to the organic medium and forming a water layer A first zone comprising: A second zone comprising an outlet for removing at least a portion of the water layer; And A pair of screw extruders having a third zone comprising an inlet for inputting water, threading members for mixing and delivery, and an outlet for removing at least a portion of the water. 10. The method of claim 9, wherein at least one of the second zone and the third zone comprises a partial weir that delays the progress of the step of transferring the pigment to the organic medium for a predetermined time period. Pair of screw extruders. 10. A pair of screw extruders according to claim 9, wherein the inlets for introducing the water soluble pigment dispersion, the destabilizing agent and the organic medium are located in one barrel of the extruder. 10. The method of claim 9, wherein the inlets for injecting the water soluble pigment dispersion and the destabilizing agent are located in a first barrel of the extruder, and the inlets for injecting the organic medium are located in a second barrel downstream of the extruder. A pair of screw extruders characterized by. Introducing a stable water-containing pigment dispersion and destabilizing agent into a pair of screw extruders; Mixing the stabilized water containing pigment dispersion and the destabilizing agent together to produce a substantially destabilized pigment; Introducing an organic medium into the pair of screw extruders; Mixing the substantially destabilized pigment and the organic medium together to produce an organic pigment dispersion layer and a water layer; And Removing at least a portion of the water layer. The method of claim 13, wherein the organic medium comprises an ink vehicle material. The method of claim 13, wherein the organic medium comprises a toner vehicle material. The method of claim 13, wherein the organic medium is a homopolymer of polyethylene, a copolymer of polyethylene, acrylonitrile butadiene styrene copolymer, polybutyene, polystyrene, polyphenylene oxide, polycarbonate, polypropylene, hydrocarbon resin, terpene ( terpene) A method for producing an organic pigment dispersion or colored product, characterized in that it comprises at least one selected from the group consisting of resins and rosin materials. The method of claim 13, wherein the organic medium comprises a polymer and a dispersant. The method of claim 13, wherein the organic medium comprises at least one selected from the group consisting of polyamides, epoxides, diolefins, polyurethanes, vinyl resins, and esterified polymeric products of diols and dicarboxylic acids, including diphenols. Characterized in that the method for producing an organic pigment dispersion or colored product. The method of claim 13, wherein after removing the water layer, silica, dispersant, charge control additive, stabilizer, wax, slip additive, lubricant, nucleator, antioxidant, biocide, ultraviolet absorber, inhibited amine light stabilizer ( hindered amine light stabilizer), an antistatic agent, a filler, and a method for producing an organic pigment dispersion or colored product, further comprising the step of injecting at least one selected from the group consisting of an adhesive resin into the extruder. The method of claim 13, wherein the stabilized water-containing pigment dispersion has a pigment content of at least about 25% by weight or more. The method of claim 13, wherein the stabilized water-containing pigment dispersion is stabilized by an ionic dispersant and the destabilizing agent is an ionic agent. 22. The method of claim 21, wherein the ionic dispersant has carboxylic acid groups in salt form, and the destabilizing agent is selected from the group consisting of protonic acids and Lewis acids. Way.

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